ドロソフィラの大きなMaf遺伝子トラフィックジャムによるpiwiの規制回路
Kuniaki Saito1, Sachi Inagaki, Toutai Mituyama
1Keio University School of Medicine, Tokyo 160-8582, Japan.
Nature
|October 9, 2009
まとめ
ドロソフィラのPIWI相互作用RNAs (piRNAs) は,レトロトランポゾンを静音化するために重要である. この研究では,トラフィックジャム (tj) 遺伝子を新しいpiRNAクラスタとして特定し,プライマリpiRNAの生体生成と体細胞の機能に関する新しい洞察を明らかにしました.
科学分野:
- * 分子生物学 * 分子生物学
- * 遺伝学について
- *RNA生物学について
背景:
- * PIWI相互作用RNA (piRNAs) は,ドロソフィラの生殖系における移植可能な要素を静止するために不可欠です.
- *piRNA生体生成には,プライマリ処理と増幅ループが含まれるが,プライマリpiRNA処理のメカニズムは不明である.
- *ドロソフィラの鍵となるPIWIタンパク質には,アルゴナウト3 (AGO3),オベージン (Aub) とピウィ (Piwi) が含まれる.
研究 の 目的:
- *ドロソフィラのプライマリpiRNA処理メカニズムを調査する.
- *新しいpiRNAクラスターとその関連遺伝子を特定する.
- * 交通渋滞 (tj) 遺伝子のpiRNA生殖における役割とそのPiwi発現との関連を解明する.
主な方法:
- * Piwi.のみを発現するドロソフィラ卵巣体細胞系におけるpiRNA処理の分析.
- * 配列と遺伝子解析を用いたpiRNAクラスターの識別.
- * tjおよびpiwi変異卵巣における遺伝子発現と細胞フェノタイプの検査.
主要な成果:
- * トラフィック・ジャム (tj) 遺伝子の位置は,その翻訳されていない領域から感覚指向のpiRNAsを生成する新しいpiRNAクラスタとして識別されました.
- * チトプラズマ核酵素をコードする遺伝子であるズッキーニは,tj由来のpiRNAsの生成に必要である.
- *性腺体細胞におけるTj機能の喪失は,生殖細胞と体細胞の混合が失敗し,Fasciclin IIIの過剰発現を引き起こし,Piwi発現を廃止する.
結論:
- * 交通渋滞 (tj) 遺伝子は,性腺体細胞で二重の役割を果たし,Piwi発現を活性化するTJタンパク質とPiwi標的を特定するpiRNAの両方を生成します.
- * 主要なpiRNA処理,特にtjのような新しいクラスターからの処理は,体組織における遺伝子発現と細胞相互作用の調節に不可欠です.
- *ピウィへのpiRNAの負荷は,細胞質で発生し,カ zucchiniは,このプロセスで役割を果たします.
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